The Vivitar Series 1 50th Anniversary lens set is a rare, gold-plated set of lenses made by Cosina.
To celebrate their 50th anniversary in 1988, Vivitar commissioned a limited edition set of two Series 1 zoom lenses. The lenses, a 28-105mm f/2.8-3.8 zoom and a 70-210mm f/2.8-4.0 zoom, were manufactured by Cosina, made of gold-plated brass, and delivered in custom-made wood cases lined with black velvet.

Serial Number: 21 of 50. Pentax K-Mount

The lenses in each set are numbered (e.g. 3 of 50) on the outer edge of the lens barrel and the serial number on the front badge is the number of the set (e.g. No.3). They were never sold to the public but given to Vivitar officials and select dealers. Over the years, some sets have passed from their original owners into the used market where they command high prices from collectors.

Some say a total of 50 sets were made, others say a total of 250 sets were made with 50 sets each for the five major countries in which Vivitar operated at the time.

In the United States, the sets were marked 'Vivitar Corporation', in Canada they were marked 'Vivitar Canada Ltd./Ltée', in France they were marked 'Hanimex-Vivitar France', in Germany they were marked 'Hanimex-Vivitar Deutschland Gmbh', and in the UK they were marked 'Vivitar United Kingdom Ltd'.

Sets containing lenses with Nikon AIS mount, Minolta MD mount, Pentax K mount, and Olympus OM mount have been documented. It is not known if sets with other mounts existed.